In many situations it is desirable to have a covering mechanism for a wide variety of uses, such as for use as a tent, awning, boat top or cover, or for covering a wide variety of other structures. Conventional coverings normally include a piece of substantially liquid impermeable cloth or other material which is merely draped over the structure to be covered, or held taut by a metal frame or the like in the case of awnings and tents. Such coverings often sag, which results in the collection of water rather the shedding of water and can impair their ultimate functioning, and often times the structures are cumbersome to place over the structure to be covered, and are difficult to remove for disposition in a position in which the covering mechanism may be readily used for subsequent covering.
According to the present invention, a simple covering mechanism is provided that is extremely versatile, which has excellent abilities for shedding water, and prevents collection of the water and subsequent sag. The covering mechanism is self-retractable into a position wherein it can be readily removed back into covering position. The covering mechanism basically comprises a self-coiling continuous sheet of substantially liquid impermeable material, having an upward bow when uncoiled, and having first and second ends. Means are provided for mounting the first end of the sheet for supporting the first end whether the sheet is in a coiled or uncoiled position, and means are provided for mounting the second end of the sheet for supporting the second end when the sheet is in an uncoiled position so that the sheet extends generally horizontally with an upward bow. The upward bow facilitates the shedding of water and prevents water collection, with subsequent sag. Due to the self-coiling nature upon release of the mechanism from its uncoiled position, it will move back to its coiled, uncovering position again readily available for movement back to its covering position.
The self-coiling continuous sheet may be constructed in a number of manners. One preferred manner is to make the sheet of an integral piece of plastic material, such as from an extruded thermoplastic polymer sheet that is heat set in its coiled position. A wide variety of commercially available plastics are suitable, including high impact polystyrene and polyethylene. The sheet may include a plurality of ribs of various profiles and cross-sections, the ribs being provided for support or for providing the self-coiling action. For instance, the sheet may comprise a flexible material (e.g. a substantially liquid impermeable cloth) covering the ribs, with the ribs supplying a force for self-coiling of the sheet. The ribs may be made of spring steel or a suitable plastic, such as an extruded thermoplastic polymeric material heat set in a coiled position. Cross springs and stiffeners may also be provided, as well as pre-stress tension or keystone arch tension when the covering mechanism is anchored in covering position to aid the supportive ability of the upward bow.
According to the method of the present invention covering of a structure is provided utilizing a self-coiling continuous sheet of substantially liquid impermeable material having first and second ends. The method includes the steps of mounting the first end of the sheet adjacent the structure so that the first end is supported whether the sheet is in a coiled or uncoiled position; operatively moving the second end of the sheet away from the first end to uncoil the sheet over the structure, until the sheet is substantially taut in an uncoiled position, extending generally horizontally with an upward bow; and then latching the second end of the sheet adjacent the structure so that the sheet is releasably maintained in its uncoiled position, covering the structure.
It is the primary object of the present invention to provide a simple, versatile, and effective covering mechanism, and a simple manner of operation thereof. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the appended claims.